What's actually causing this
Toilets run when water continuously trickles from the tank into the bowl. The two most common culprits are a worn-out flapper that doesn't seal properly, and a fill valve that's stuck open or set too high.
What you'll need
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- Toilet flapper kit Shop →
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Step-by-step fix
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1
Diagnose the problem
Lift the tank lid and add a few drops of food coloring. If color appears in the bowl within 10 minutes without flushing, the flapper is leaking.
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2
Turn off the water supply
Turn the shutoff valve behind the toilet clockwise. Flush once to empty the tank.
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3
Replace the flapper
Unhook the old flapper from the overflow tube pegs. Snap the new flapper in place and reconnect the chain — leave about half an inch of slack.
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4
Adjust the fill valve
If water is running over the overflow tube, the water level is too high. Adjust the float arm or float ball downward until the water sits 1 inch below the top of the overflow tube.
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5
Turn water back on and test
Slowly open the shutoff valve. Let the tank fill and listen for any continued running after the fill cycle completes.
In Miami, tap water is very hard (250–320 ppm). Miami's water is hard, sourced from limestone aquifers. Mineral deposits are severe. Salt intrusion from the ocean is a growing concern in coastal areas. Corrosion is accelerated by humidity and salt air. Water softeners or filters are very common.
Plumbers in Miami typically charge $110–180/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
Florida has strict licensing (myfloridalicense.com). Plumbing requires state-licensed plumber. Homeowner exemptions are very limited — only repairs on own home with own labor.
Majority post-1980s construction elevated for flood risk. Copper is standard. Hard water and salt corrosion accelerate fixture failure. Slab-on-grade with salt intrusion risk. Storm surge can flood plumbing systems. Backflow prevention devices are common.
DIY in Miami: Miami's strict Florida licensing requirements, hurricane codes, and environmental hazards make DIY repairs very restricted. Homeowners should hire licensed professionals for plumbing, electrical, and HVAC. Coastal properties require special knowledge and materials.
- The tank or bowl has visible cracks.
- The toilet rocks or is loose at the base — this may indicate a wax ring failure.
- Water appears on the floor around the base after flushing.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Miami.
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